If I have do not disturb set to "until next alarm", it doesn't actually get disabled on the next alarm if soundabout is enabled. This is important when it's set to silent until next alarm since it won't actually trigger at the next alarm.

actually, it's still broken, although it only seems to be broken overnight/for early alarms.

I can set an alarm for 6am and then (at, say, 10pm) set my phone in any ring mode (silent, priority, or alarms only) 'until next alarm'. The alarm always triggers, but the specific ring mode isn't disabled upon the alarm going off.